1) Computer simulation of previously studied patients with shock lung will continue. Since these patients had arterial hypoxemia while breathing high oxygen concentrations, we will treat inspired alveolar ventilation (instead of expired alveolar ventilation) as the constant factor. Expired alveolar ventilation decreases in malfunctioning lung tissue as inspired oxygen concentration is increased at a constant inspired alveolar ventilation. The proposed approach is appropriate because the mechanical ventilators used in our shock lung patients delivered a constant inspired ventilation, not a constant expired ventilation. 2) Studies will be performed in patients with asthma in the emergency room on the relationship between the concentrations of aminophylline and cortisol in the blood and the degree of airway obstruction. The peak flow rate will be repeatedly measured. Treatment will be initiated with aminophylline and, if this is not sufficient, will be continued with one large dose of intravenous hydrocortisone. 3) Intravenous oleic acid will be given to anesthetised dogs to induce the shock lung syndrome and/or pulmonary edema. Intravenous manuital will be given to see whether its osmotic properties have any effect on the disease process as judged by arterial blood gases, pulmonary compliance and pulmonary artery pressure.